Robotic safety stop for automated storage library

ABSTRACT

A safety stop mechanism for an automated storage library in which a connector has first and second ends. The first end is configured to contact a door of the automated storage library when the door is in at least a first position. A safety stop is connected to the second end of the connector and adapted to move from a down position to an up position. The safety stop is in the down position when the door is in the first position allowing for travel of the robotic accessor over the safety stop.

CROSS REFERENCE TO RELATED APPLICATIONS

This Application is a Continuation of U.S. Patent Application Ser. No.13/458,811, filed on Apr. 27, 2012, which is a Continuation of U.S.Patent Application Ser. No. 12/687,333, filed on Jan. 14, 2010.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates in general to computers, and moreparticularly to apparatus and method embodiments directed to anautomatically activated robotic safety stop for automated storagelibraries in a computing storage environment.

2. Description of the Related Art

Automated data storage libraries are known for providing cost effectivestorage and retrieval of large quantities of data. The data in automateddata storage libraries is stored on data storage media that are, inturn, stored on storage shelves or the like inside the library in afashion that renders the media, and its resident data, accessible forphysical retrieval. Such media is commonly termed “removable media”.Data storage media may comprise any type of media on which data may bestored and which may serve as removable media, including but not limitedto magnetic media (such as magnetic tape or disks), optical media (suchas optical tape or disks), electronic media (such as PROM, EEPROM, flashPROM, Compactflash™, Smartmedia™, Memory Stick™, etc.), or othersuitable media. Typically, the data stored in automated data storagelibraries is resident on data storage media that is contained within acartridge and referred to as a data storage media cartridge. An exampleof a data storage media cartridge that is widely employed in automateddata storage libraries for mass data storage is a magnetic tapecartridge.

In addition to data storage media, automated data storage librariestypically contain data storage drives that More data to, and/or retrievedata from, the data storage media. The transport of data storage mediabetween data storage shelves and data storage drives is typicallyaccomplished by one or more robotic accessors (hereinafter termed“accessors”). Such accessors have grippers for physically retrieving theselected data storage media from the storage shelves within theautomated data storage library and transport such media to the datastorage drives by moving in the horizontal “X” and vertical “Y”directions.

SUMMARY OF THE INVENTION

In many automated tape libraries today, multiple robotic accessors areused to provide customers high availability library systems withredundant robotic mechanisms. A common technique for these highavailability library systems is to have two robotic accessors operate onthe same rail system. When a failure occurs on one of the roboticaccessors, it may be moved into a service area of the library while theother robotic accessor continues to perform operations on the activeportion of the library. In order to service the failed accessor, asafety barrier or “stop” must be provided to keep the active accessorfrom entering the service area of the library while the servicepersonnel is in this space. The safety barrier or stop must beoperational in the worst case event where the second active roboticaccessor were to run out of control trying to enter the area where theservice personnel are servicing the failed robotic accessor. Typicallythis safety barrier or stop is a door that is slid into place orassembled into place by the service personnel upon opening the door tothe automated tape library and entering the robotic accessor space.

One drawback of the above solution is that if the safety barrier or stopis not installed correctly by the service personnel, the library willeither not resume work with the one non-failed accessor or, the librarywill resume its operation and create a possible safety exposure for theactive accessor being able to crash through the incorrectly installedsafety barrier or stop. Another drawback of this solution is that thereis some time required by the service personnel to activate or installthe safety barrier or stop. This is not desirable in today's world whereservice calls are needed to be as short as possible to keep warranty andservice costs to a minimum. Accordingly, a need exists for a safety stopmechanism that minimizes or eliminates the drawbacks previouslydescribed.

In view of the foregoing, method embodiments directed to a safety stopmechanism for a robotic accessor in an automated storage library areprovided. In one such embodiment, by way of example only, a connectorhas first and second ends. The first end is configured to contact a doorof the automated storage library when the door is in at least a firstposition. A safety stop is connected to the second end of the connectorand adapted to move from a down position to an up position. The safetystop is in the down position when the door is in the first position toallow for travel of the robotic accessor over the safety stop.

In addition to the foregoing exemplary embodiment, various additionalapparatus and method embodiments are disclosed and provide relatedadvantages.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the advantages of the invention will be readilyunderstood, a more particular description of the invention brieflydescribed above will be rendered by reference to specific embodimentsthat are illustrated in the appended drawings. Understanding that thesedrawings depict embodiments of the invention and are not therefore to beconsidered to be limiting of its scope, the invention will be describedand explained with additional specificity and detail through the use ofthe accompanying drawings, in which:

FIG. 1 illustrates an isometric view of an automated data storagelibrary adaptable to implement an embodiment of the present invention,with the view specifically depicting a library having a left handservice bay, multiple storage frames and a right hand service bay;

FIG. 2 illustrates an isometric view of an automated data storagelibrary adaptable to implement various aspects of the present inventionand claimed subject matter, with the view specifically depicting anexemplary basic configuration of the internal components of a library;

FIG. 3 illustrates an additional isometric view of a portion of theautomated data storage library shown in FIG. 2, including a roboticsafety stop embodiment of the present invention in a side view;

FIG. 4 illustrates an additional isometric view of an additional portionof the automated data storage library shown in FIG. 2, including anadditional robotic safety stop embodiment of the present invention in afront view;

FIG. 5 illustrates an isometric view of an exemplary embodiment of arobotic safety stop mechanism in a side view, depicting an integratedsafety stop in a down position;

FIG. 6 illustrates a partial section view of the robotic safety stopmechanism embodiment depicted in FIG. 5;

FIG. 7 illustrates the robotic safety stop mechanism embodiment depictedin FIG. 5 with the integrated safety stop in an up position; and

FIG. 8 illustrates an additional partial section view of the roboticsafety stop mechanism embodiment depicted in FIG. 5 with the integratedsafety stop in an up position.

DETAILED DESCRIPTION OF THE DRAWINGS

The invention will be described as embodied in an automated magnetictape library storage system for use in a data processing environment.Although the invention shown uses magnetic tape cartridges, one skilledin the art will recognize the invention equally applies to optical diskcartridges or other removable storage media and the use of eitherdifferent types of cartridges or cartridges of the same type havingdifferent characteristics. Furthermore the description of an automatedmagnetic tape storage system is not meant to limit the invention tomagnetic tape data processing applications as the invention herein canbe applied to any media storage and cartridge handling systems ingeneral.

Turning now to the Figures, FIGS. 1 and 2 illustrate an automated datastorage library 10 which stores and retrieves data storage cartridgescontaining data storage media (not shown) in storage shelves 16. It isnoted that references to “data. storage media” herein refer to datastorage cartridges, and for purposes herein the two terms are usedsynonymously. An example of an automated data storage library that mayimplement the present invention, and has a configuration as depicted inFIGS. 1 and 2, is the IBM® 3584 UltraScalable Tape Library.

The library of FIG. 1 comprises a left hand service bay 13, one or morestorage frames 11, and right hand service bay 14. As will be discussed,a frame may comprise an expansion component of the library. Frames maybe added or removed to expand or reduce the size and/or functionality ofthe library. Frames may comprise additional storage shelves, drives,import/export stations, accessors, operator panels, etc.

FIG. 2, following, shows an example of a storage frame 11, which is thebase frame of the library 10 and is contemplated to be the minimumconfiguration of the library. In this minimum configuration, there isonly a single accessor (i.e., there are no redundant accessors) andthere is no service bay. While the depicted embodiment shows a singleaccessor, one of ordinary skill in the art will appreciate that in manyconfigurations, an additional (redundant) assessor is provided with thefirst accessor along a single rail system. Various aspects of thepresent invention will be applicable to the minimum configuration, theredundant configuration just described, and other configurations as oneof ordinary skill in the art will appreciate.

The library 10 is arranged for accessing data storage media in responseto commands from at least one external host system (not shown), andcomprises a plurality of storage shelves 16, one front wall 17 and rearwall 19 for storing data storage cartridges that contain data storagemedia; at least one data storage drive 15 for reading and/or writingdata with respect to the data storage media; and a first accessor 18 fortransporting the data storage media between the plurality of storageshelves 16 and the data storage drive(s) 15 (here again, a redundant,second accessor may also be similarly configured). The data storagedrives 15 may be optical disk drives or magnetic tape drives, or othertypes of data storage drives as are used to read and/or write data withrespect to the data storage media. The storage frame 11 may optionallycomprise an operator panel 12 or other user interface, such as aweb-based interface, which allows a. user to interact with the library.The storage frame 11 may optionally comprise an upper I/O station 24and/or a lower station 25, which allows data storage media to beinserted into the library and/or removed from the library withoutdisrupting library operation. The library 10 may comprise one or morestorage frames 11, each having storage shelves 16 accessible by firstaccessor 18.

As described above, the storage frames 11 may be configured withdifferent components depending upon the intended function, Oneconfiguration of storage frame 11 may comprise storage shelves 16, datastorage drive(s) 15, and other optional components to store and retrievedata from the data storage cartridges. The first accessor 18 comprises agripper assembly 20 for gripping one or more data storage media and mayinclude a bar code scanner 22 or other reading system, such as acartridge memory reader or similar system, mounted on the gripperassembly 20, to “read” identifying information about the data storagemedia.

Referring still to FIG. 2, a robotic safety stop mechanism 30 isdepicted mounted to a base structure of the frame 11 as will be furtherdescribed. The depicted embodiment of the safety stop mechanism 30,along with other representative exemplary embodiments, provide forautomatic activation when service personnel opens the door to the frame11, again as will be further described. This automatic activation of thesafety stop prevents the service personnel from being able toincorrectly install the safety barrier or stop, as well as prevents thepersonnel from forgetting to install the safety barrier or stop. A lackof installation, in some implementations for example, may causesignificant down time for the library 10. Finally, the illustratedembodiments allow for rapid activation of the safety stop to maintain aminimal amount of required service time.

In one exemplary embodiment, the safety stop mechanism 30 operates byuse of a spring-loaded plunger connected to a moveable safety stop forthe robotic accessor. The safety stop and its associated mechanism arelocated at the bottom of the automated tape library frame. During normallibrary operation, the safety stop is in a down position, which allowsthe robotic accessors to pass over the safety stop without anyinterference. This down position is maintained by having thespring-loaded plunger in contact with the closed library end door. Whenthe end door is opened, the spring-loaded plunger activates the safetystop moving it to the up position, as will be further described.

When a failure occurs on one of the robotic accessors in one exemplaryconfiguration, the robotic accessor is moved into the service area ofthe library either by moving itself or being pushed by the othernon-failed, or active, robotic accessor. The failed accessor remains inthis location until the service personnel arrives at the library toservice the failed robotic accessor. When the service personnel opensthe door to service the accessor, the spring-loaded plunger is able toextend toward the opening created by opening the end door of thelibrary. This motion and the coupling to the safety stop, allows thesafety stop to be lifted into its activated position such that theactive accessor cannot crash through the safety stop entering the areawhere the service action is taking place. A sensor may be placed on themechanism to sense that the safety stop is fully activated. The activeaccessor will not be able to move and the library will be down untilthis sensor on the mechanism is triggered.

After completing the service action, the service personnel closes theend door of the library and the spring-loaded plunger again is pushed into the library, returning the safety stop to its inactive down positionallowing both robotic accessors to pass over the top of the stop fornormal library operation. The design of the illustrated embodimentsallows for an integrated safety stop to be installed on either end ofthe library string, such that two of these mechanisms are installed, oneon each side of the library, so that if a failure occurs on either ofthe two robotic accessors, a safety stop mechanism is in place toperform the required service action.

One of ordinary skill in the art will appreciate that other similarembodiments may be contemplated where, commensurate with a degree ofmovement of a door of the library frame, a corresponding movement isinduced in a safety stop device such that the device engages from aninactive state to an active state. For this reason, while many of theillustrated embodiments in the instant description make reference to anaforementioned spring-loaded plunger, some of the following claimedsubject matter refers to a “connector” adapted to make contact with thedoor of the library frame.

FIG. 3, following, shows an isometric, side view of a portion of thelibrary frame 11 depicted earlier in FIGS. 1 and 2. In the depictedrepresentation, the end door 32 of the library is ajar, allowing thespring-loaded plunger 34 to travel horizontally in substantially the +xdirection (represented rightward along arrow 27), and activating thesafety stop 30 of the safety stop mechanism 31 in an up position as willbe further described.

FIG. 4 shows an isometric, front view of an additional portion of thelibrary frame 11. Here, the safety stop mechanism 31 is seen in a frontview. The spring-loaded plunger 34 emerges from an opening 35 placed ina sidewall 33 of the frame 11. The safety stop mechanism 31 is securelymounted to a base structure 37 of the frame 11. In the depictedrepresentation, the robotic accessor 18 is shown in the background. Whenthe safety stop 30 is in an up position as shown, movement of therobotic accessor 20 is prohibited beyond (forward in the instantrepresentation) the safety stop 30 as one of ordinary skill in the artwill appreciate.

Turning now to FIG. 5, an isometric view of the safety stop mechanism isshown, where the safety stop is in a down position (represented by arrow20). In the depicted embodiment, the safety stop mechanism 31 includes aspring-loaded plunger 34 configured to contact an end door of thelibrary. Arrow 42 represents compressive force applied by the door tothe spring-loaded plunger 34, causing the plunger 34 to travel laterallyin the −x direction (represented leftward along arrow 27). Pressure onthe plunger 34 causes the safety stop 30 to move from an up position tothe down position shown by arrow 21.

A housing 36 encloses the spring-loaded plunger 34 and spring mechanismas will be further described. In the depicted embodiment, openings 37may be adapted to receive a mounting screw to attach the housing 36 to abase structure of the frame as previously described. A sensor device 40and flag 38 may be connected to a portion of the housing 36 and thesafety stop 30 as shown for detecting when the safety stop 30 is in anup position and/or down.

FIG. 6, following, depicts a partial section view of the safety stopmechanism 31 with the safety stop 30 in a down position (indicated byarrow 21). A rubber bumper 52 is connected to safety stop 30 as shown tocushion engagement of the stop 30 with the robotic accessor. In theinstant depiction, a portion of the housing 36 is cut away, allowing forview of the spring-loaded plunger 34. Two stamp out portions of thehousing 36, surfaces 47 and 49 are shown. Surface 47 provides a backstopfor the spring mechanism 46 to rest, while surface 49 acts as a guide toprovide alignment of the plunger 34.

As is more clearly shown in the partial section view, a u-shaped bracketstructure 48 is attached to an end of the plunger 34. The bracket 48 isadapted to slide along a portion of the safety stop 30 as the safetystop 30 pivots about pin 44. Compressive pressure (again denoted byarrow 42) on the plunger 34 exerted by a side door of the frame causesthe plunger 34 to travel laterally substantially in the −x direction(again represented leftward along arrow 27), also directing lateralforce along the bracket 48 and to attachment pin 50, transferring suchforces to the safety stop 30. As one of ordinary skill in the art willappreciate, the compressive pressure is transferred to the stop 30,causing the stop to move from an up position to a down position asindicated, while also compressing the spring 46.

FIG. 7 depicts the safety stop mechanism 31 with the safety stop 30 inan up position (denoted by arrow 21). As is more clearly shown, a camtrack 56 embedded in the safety stop 30 allows for the pin 50 (FIG. 6)to move, such that when a lateral force in the +x direction (caused byexpansion of the spring mechanism 46, FIG. 6, and again representedrightward along arrow 27) is exerted on the pin 50 by the plunger 34(denoted by arrow 58), the safety stop 30 is pulled from a down positionto the up position as shown. Again, sensor 40 and flag 38 are shown suchthat the sensor 40 is blocked by the flag 38, indicating to theautomated control system that the safety stop is activated. Housing 36is substantially wide enough (as indicated by width 54) to accommodate awidth of a failed robotic accessor.

FIG. 8, following, depicts an additional partial section view of thesafety stop mechanism 31, where the safety stop 30 is in an up position(again as denoted by arrow 21). A more detailed view of the cam track 56is shown, along with the pin 50 and pin 44 allowing the safety stop 30to pivot. As is shown, the spring mechanism 46 is released by expansionof the plunger 34 in the lateral +x direction (again denoted by arrow58, and again represented by rightward travel along the arrow 27).

While one or more embodiments of the present invention have beenillustrated in detail, one of ordinary skill in the art will appreciatethat modifications and adaptations to those embodiments may be madewithout departing from the scope of the present invention as set forthin the following claims.

What is claimed is:
 1. A safety stop mechanism for a robotic accessor inan automated storage library, comprising: a connector having first andsecond ends, the first end configured to contact a door of the automatedstorage library when the door is in at least a first position; and asafety stop connected to the second end of the connector and adapted tomove from a down position to an up position, the safety stop in the downposition when the door is in the first position to allow for travel ofthe robotic accessor over the safety stop.
 2. The safety stop mechanismof claim 1, wherein the connector is adapted to travel laterallycorresponding to movement of the door between the first position and asecond position, consequently moving the safety stop from the downposition to the up position, the up position preventing travel of therobotic accessor beyond the safety stop.
 3. The safety stop mechanism ofclaim 2, wherein the first position of the door is closed and the secondposition of the door is open.
 4. The safety stop mechanism of claim 1,further including a bracket, pinned through the safety stop, to connectthe safety stop to the second end of the connector.
 5. The safety stopmechanism of claim 4, further including a cam track integrated into thesafety stop, at least a portion of the pinned bracket traveling alongthe cam track as the safety stop is moved from the down position to theup position.
 6. The safety stop mechanism of claim 1, wherein theconnector is a spring-loaded plunger.
 7. The safety stop mechanism ofclaim 1, wherein the connector is at least partially enclosed by ahousing.
 8. The safety stop mechanism of claim 7, further including apin connecting at least a portion of the safety stop to the housing,wherein the safety stop is adapted for pivoting from the down positionto the up position about the pin.
 9. The safety stop mechanism of claim7, further including a sensor device connected to the housing, whereinthe sensor device is adapted for detecting the safety stop in at leastone of the up position and the down position.
 10. The safety stopmechanism of claim 7, wherein the housing is adapted for mounting to abase structure of the automated storage library.
 11. A safety stopmechanism for a robotic accessor in an automated storage library,comprising: a housing; a plunger, spring-loaded to a portion of thehousing, and having a first end adapted to contact a door of theautomated storage library when the door is in at least a first position;and a safety stop connected to an end of the plunger and adapted to movefrom a down position to an up position, the safety stop being in thedown position when the door is in the first position to allow for travelof the robotic accessor over the safety stop.
 12. The safety stopmechanism of claim 11, wherein moving the door between the firstposition and a second position releases the plunger to allow for lateraltravel, inducing movement of the stop from the down position to the upposition to prevent travel of the robotic accessor beyond the safetystop.
 13. The safety stop mechanism of claim 12, wherein the firstposition of the door is closed and the second position of the door isopen.
 14. The safety stop mechanism of claim 11, further including abracket, pinned through the safety stop, to connect the safety stop tothe end of the plunger.
 15. The safety stop mechanism of claim 11,further including a cam track integrated into the safety stop, at leasta portion of the pinned bracket traveling along the cam track as thesafety stop is moved from the down position to the up position.
 16. Thesafety stop mechanism of claim 11, further including a pin connecting atleast a portion of the safety stop to the housing, wherein the safetystop is adapted for pivoting from the down position to the up positionabout the pin.
 17. The safety stop mechanism of claim 11, furtherincluding a sensor device connected to the housing, wherein the sensordevice is adapted for detecting the safety stop in at least one of theup position and the down position.
 18. The safety stop mechanism ofclaim 11, wherein the housing is adapted for mounting to base structureof the automated storage library.
 19. A method of manufacturing a safetystop mechanism for a robotic accessor in an automated storage library,comprising: providing a connector having first and second ends, thefirst end configured to contact a door of the automated storage librarywhen the door is in at least a first position; and providing a safetystop connected to the second end of the connector and adapted to movefrom a down position to an up position, the safety stop in the downposition when the door is in the first position to allow for travel ofthe robotic accessor over the safety stop.
 20. The method of manufactureof claim 19, wherein the connector is adapted to travel laterallycorresponding to movement of the door between the first position and asecond position, consequently moving the safety stop from the downposition to the up position, the up position preventing travel of therobotic accessor beyond the safety stop.
 21. The method of manufactureof claim 19, further including providing a sensor device adapted todetect the safety stop in at least one of the up position and the downposition.